Discoverer/Coronaseries satellites

This page contains philatelic information on the Discoverer/Corona-series satellites. Catalog numbers, years of issue, and notes on the satellites featured are given when available. If readers know of additional information or images, please contact the authors using the e-mail addresses at the bottom of this page.

The Discoverer-series, also known as Corona satellites, were later declassified as the first KeyHole (KH) reconnaissance satellites.

1Pioneer-5 and Explorer-6 were similar "paddlewheel" satellites. It is believed that Explorer-6 contained two short antennas on its "top", whereas Pioneer-5 contained only a single short antenna. When there are no antennas on top, the distinction is unclear, but of the two, Pioneer-5 is assumed.